diff --git a/sys/amd64/vmm/vmm_dev.c b/sys/amd64/vmm/vmm_dev.c
index cae15d7059cb..5214cd3f1447 100644
--- a/sys/amd64/vmm/vmm_dev.c
+++ b/sys/amd64/vmm/vmm_dev.c
@@ -629,10 +629,12 @@ vmmdev_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag,
 
 				p = (uint8_t *)vmrun->cpuset +
 				    sizeof(cpuset_t);
-				while (error == 0 &&
-				    p < (uint8_t *)vmrun->cpuset +
+				while (p < (uint8_t *)vmrun->cpuset +
 				    vmrun->cpusetsize) {
-					error = subyte(p++, 0);
+					if (subyte(p++, 0) != 0) {
+						error = EFAULT;
+						break;
+					}
 				}
 			}
 		}